Depends on the premise of the question. Am I stuck on an island surrounded by salt water for the rest of my life with an unlimited supply of 5 beers? Or is it the 5 best beers I've ever had, knowing I might not want to consume them in quantity?

__________________Martin Luther -

"Whoever drinks beer he is quick to sleep; whoever sleeps long does not sin; whoever does not sin enters Heaven! Thus let us drink beer"

I'm going to count only universally findable product since you said commercial..
Orval
North Coast Old Rasputin
Oskar Blue's Dale's Pale Ale
Great Divide Titan
Rodenbach Grand Cru
And if there were 6 I would add Anchor Steam
If I went rarer I would have to think a lot longer..I'd almost call this my top 5 go-to-commercial craft list-Beers I could typically find in any good bottle shop in most states